Water heater or boiler



NOV. 28, 1933. JJFOUNTAlN 1,937,059

WATER HEATER OR BOILER Filed Sept. 22. 19:51

Patented Nov. 28, 1933 UNITED STATES PATENT OFFICE Application September 22, 1931, Serial No. 564,320, and in Great Britain September 23,

1 Claim.

This invention relates to water heaters or boilers adapted to be heated by exhaust gases from internal combustion engines, and more particularly to water heaters or boilers of the type com- 5 prising an outer shell and an inner shell forming between them the water space of the boiler, a plurality of thimbles or cross tubes extending from said water space radially into or across the space within the inner shell, and a tubular bafile partitigning the space within the inner shell into two gas passes, so as to provide for the flow of the exhaust gases from the engine either first across the thimbles or cross tubes and thence through the tubular baffle or vice versa.

The invention has for its object to provide an improved construction of water heater or boiler of this type permitting the utilization either separately or together of the heat of exhaust gases of combustion or of steam and of heat generated electrically. The improved boiler is thus well adapted for use where Diesel engines or like engines are installed and where electric current in excess of requirements is on occasions available from electrical accessories, as for instance in certain types of locomotives and in tramp and other steamships.

In accordance with the invention within the water space formed between the bottom of the I inner shell and the bottom of the outer shell there are disposed a plurality of electric immersion heaters adapted to be supplied with current from dynamos or other sources of heating current. The outer and inner shells are secured together at the upper end only so as to permit expansion of one relatively to the other with the consequence that the boiler can be run dry and used for instance as a silencer for exhaust gases without detriment.

One embodiment of the invention is illustrated in the accompanying drawing in vertical section. Referring to the drawing, A is the outer shell of the boiler from which is spaced the inner shell B which is fitted with a plurality of cross tubes or thimble tubes B in the usual manner. In the embodiment shown, C denotes the inlet for the exhaust gases and D a central tubular bafile disposed axially within the inner shell and ensuring the flow of the gases in the direction indicated by the arrows from the exhaust gas inlet C to the exhaust gas outlet F. The bottom of the inner shell B, which shell forms with the outer shell the water space of the boiler, is spaced from the bottom of the outer shell and in the intervening space are disposed a plurality of electric immersion heaters G, suitably in spaced rows,

which may be used either alone or in conjunction with the exhaust combustion gases or waste steam to generate steam in the boiler. The exhaust gases or waste steam may also be used alone for this purpose. H denotes the usual circulation bafile provided in such boilers.

It will be understood that, since the inner shell is suspended within the outer shell, one shell can expand freely relatively to the other. Consequently, the boiler may be used with safety in dry state as a silencer for exhaust gases.

Where in lieu of thimbles cross tubes are provided such cross tubes will extend around the central bafile D.

I claim:

A water heater or boiler of the type referred to, and permitting the utilization of the heat of exhaust gases of combustion, of the heat of steam, and of heat generated electrically, simultaneously or separately, thus providing a combined flash boiler and electrical-boiler, and adapted for use also as a silencer, comprising in combination an outer shell, an inner shell suspended within said outer shell in such manner as to be expansible freely of the other shell and spaced therefrom at the sides and bottom to afford a water space which when the boiler is used as a silencer may be empty of water, the spacing from the bottom being great in relation to the spacing from the sides so as to provide a large water capacity at the bottom, tubular means extending from said water space into the space within said inner shell, a tubular baiile disposed within said inner shell and forming with said inner shell two gas passes, and a plurality of electric immersion heaters disposed in said water space of large capacity remote both from the bottom of the inner shell and from the bottom of the outer shell, the annular space between the inner and outer shells constituting a flash boiler, and the water space between the bottom of the inner shell and the bottom of the outer shell constituting an electrical boiler with a water capacity, and the surfaces being wettable to any desired extent, whereby to obtain a fine regulation of the rate of evaporation.

HOWARD JOHN FOUNTAIN. 

